Searchable Encrypted Data Sharing Method and System Based on Blockchain and Homomorphic Encryption

2. The searchable encrypted data sharing method based on blockchain and homomorphic encryption according to claim 1, wherein the cloud server is configured to store the ciphertext of the sensitive data.

3. The searchable encrypted data sharing method based on blockchain and homomorphic encryption according to claim 1, wherein the user randomly generates a public-private key pair according to the system public parameters, and the generation of the public-private key pair is independent from a trusted third party.

4. The searchable encrypted data sharing method based on blockchain and homomorphic encryption according to claim 1, wherein the cloud server assigns real identity information to the user, and the user uses pseudo-identity information to upload data and request data operations.

5. The searchable encrypted data sharing method based on blockchain and homomorphic encryption according to claim 1, wherein from top to bottom, the alliance chain comprises: an application layer, a contract layer, an incentive layer, a consensus layer, a network layer and a data layer; the data layer is used to store transaction logs and transaction-related contents, that is, the pseudo-identity information of the data owner, ciphertext index and keyword ciphertext; the consensus layer adopts a practical Byzantine fault-tolerance (PBFT) consensus algorithm.